From POEM to POET: Applications and perspectives for submucosal tunnel endoscopy.

Recent advances in submucosal endoscopy have unlocked a new horizon for potential development in diagnostic and therapeutic endoscopy. Increasing evidence has demonstrated that peroral endoscopic myotomy (POEM) is not only clinically feasible and safe, but also has excellent results in symptomatic relief of achalasia. The success of submucosal endoscopy in performance of tumor resection has confirmed the potential of this new area in diagnostic and therapeutic endoscopy. This article reviews the current applications and evidence, from POEM to peroral endoscopic tunnel resection (POET), while exploring the possible future clinical applications in this field.